Rubidium transitions as wavelength reference for astronomical Doppler spectrographs

Authors:
  • DRDmytro Rogozin
    Dmytro Rogozin
  • TFTobias Feger
    Tobias Feger
  • CSChristian Schwab
    Christian Schwab
  • YGYulia V. Gurevich
    Yulia V. Gurevich
  • GRGert Raskin
    Gert Raskin
  • DCDavid W. Coutts
    David W. Coutts
  • JSJulian Stuermer
    Julian Stuermer
  • ASAndreas Seifahrt
    Andreas Seifahrt
  • TFThorsten Fuehrer
    Thorsten Fuehrer
  • TLThomas Legero
    Thomas Legero
  • HWHans van Winckel
    Hans van Winckel
  • SHSam Halverson
    Sam Halverson
Preprint
Publisher website
Google Scholar
Abstract
Precise wavelength calibration is a critical issue for high-resolution spectroscopic observations. The ideal calibration source should be able to provide a very stable and dense grid of evenly distributed spectral lines of constant intensity. A new method which satisfies all mentioned conditions has been developed by our group. The approach is to actively measure the exact position of a single spectral line of a Fabry-Perot etalon with very high precision with a wavelength-tuneable laser and compare it to an extremely stable wavelength standard. The ideal choice of standard is the D2 absorption line of Rubidium, which has been used as an optical frequency standard for decades. With this technique, the problem of stable wavelength calibration of spectrographs becomes a problem of how reliably we can measure and anchor one etalon line to the Rb transition. In this work we present our self-built module for Rb saturated absorption spectroscopy and discuss its stability.
All Related Versions